In the operation of certain tilting barrel Browning-type semiautomatic pistols or handguns, a slide element is cycled relative to a frame between battery and retired positions via the firing of cartridges. As a cartridge is fired, the slide is driven rearward into the retired position. A spring provides for the return of the slide in the forward direction and in the process replenishes the handgun with a fresh cartridge stripped from a magazine.
As the slide is driven rearward, an aperture in the front of the slide allows the slide to move rearward around the barrel. The barrel is supported at its rearward end via a lug on the barrel, the rearward portion of the lug being ramped to receive the next cartridge in preparation for firing. Tolerance between the slide and the lug allows the slide and the barrel to be decoupled as the slide moves rearward. When the slide moves rearward, the forward end of the barrel moves upward, which facilitates the feeding of a fresh cartridge.
In order to locate the position of the barrel within the slide from shot to shot, clearances must exist between the outer diameter of the barrel and the inner diameter of the aperture of the slide through which the barrel is received every time the slide is cycled (either manually or during firing). Various methods exist for locating the barrel within the aperture. One method incorporates spherical bushings or bearings into the aperture of the slide at the points of contact. Such bushings or bearings, while being effective to consistently locate the barrel during cycling, generally complicate the structure of the handgun, add mass, are costly, and make the gun difficult to assemble. The use of spherical bushings typically requires that large tolerances exist between the points of contact on the slide and the barrel.